Pilots often stare in disbelief the first time they fly over the town of General Levalle in Argentina’s Córdoba province. A strange design breaks the monotony of the endless pampa below. It looks like a giant crop circle in the shape of an acoustic guitar. In fact it is made of cypress and eucalyptus trees instead of cereal crops, and it is almost a kilometer long. “It’s incredible to see a design that was so meticulously laid out so far below. There’s nothing else like it,” says Gabriel Pindek, a commercial pilot for Argentina‘s Austral airline.

Behind this great guitar of the Argentine pampa, and its 7,000 trees, is a love story that has left its mark on the family at its center and everyone who knows them. You are next, prepare to be marked. The guitar shaped tree grove in the work of Pedro Martin Ureta, a 70-year old local farmer. His inspiration was his late wife Graciela Yraizoz, who died in 1977 at the age of 25.

Mr. Ureta, the scion of a ranching family with deep roots in the area, was quite the bohemian in his youth. He traveled to Europe and hobnobbed with artists and revolutionaries. After coming home in the late 1960s, the then-28-year old became captivated by Graciela, who was just 17 years old. The local priest almost refused to perform the wedding, Ureta recalls: He didn’t think the rancher was sufficiently committed to loving Ms. Yraizoz “all the days” of his life. But Ureta proved to be extraordinarily devoted to his wife, their friends and children say. The marriage was happy, but brief.

“My mother was very industrious, she had lots of projects” says Soledad (38), one of the four children produced by the marriage. “She sold clothes and helped my father get ahead.” One day during a flight over the plains of the pampa, Graciela noticed a farm that, through a fluke of topography, looked a bit like a milking pail, her children say. That’s when she started thinking designing the family’s own farm in the shape of a guitar, an instrument she loved.

“My father was very young, and was occupied with his work and his own plans,” says his youngest child, Ezequiel, who is 36. “He would tell her ‘We’ll talk about it later.'” But Graciela didn’t have much time to wait. One day in 1977 she fainted. She had suffered a brain aneurism, a weakened blood vessel that eventually burst. She died shortly after; carrying what would have been the couple’s fifth child.

Today, Ureta says his wife’s death pointed his life in a more philosophical direction. He took a step back, read about Buddhism, and never stopped thinking of her. Mr. Ureta paraphrases a line by Argentine folk guitarist and writer Atahualpa Yupanqui which described his state of mind: “I galloped a lot, but I still arrived late all the same.”

A few years after Graciela’s death, Ureta decided to comply with her wishes about the design of the ranch. The landscapers he consulted were predictably nonplussed, so he decided to do the job himself. The outline of the guitar and the central star shaped sound hole, is made of cypress trees. For the guitar’s chords, Ureta planted six rows of eucalyptus trees whose bluish tone contrasted pleasantly with the dark green of the outline.

Planting the guitar was a family affair, and making the young saplings grow was a difficult chore requiring dedication. Hares and wild guinea pigs would destroy the fragile plants. “It is a semi-arid area with strong winds and droughts” says Ureta. “I had to plant and replant and I almost gave up on the project.” Finally, Ureta had an saving idea: he used scrap metal and other materials to build protective sleeves around the young trees.

Maria Julia, Ureta’s 39-year-old daughter, says that when the trees finally began to grow, she felt her mother had returned to life. While he was taking care of the trees, Ureta was also raising four children. Every day, he drove the kids to school in his pickup truck. When the truck got stuck in the mud during rainy season, he used a horse to pull it out. Today, the oldest son, Ignacio, 42, is an engineer; Maria Julia is a pharmaceutical representative; Soledad is a special education teacher; and Ezequiel is a veterinarian. There are nine grandchildren.

Ureta waited a long time after Graciela’s death before starting another serious relationship, his children say. In the 1990s, he started going out with Maria de los Angeles Ponzi, who runs the town pharmacy. They didn’t marry, but they have an 11-year-old daughter, Manuela. Maria says she appreciates the beauty of the tribute to her partner’s first wife. Mr. Ureta himself has never seen his great guitar from the sky, except in photos. He’s afraid of flying. He prefers to imagine it. After all, he built it as an offering of love, not as an object to admire.